Project summary We propose to demonstrate the feasibility of softening multi-shank microelectrode arrays which are stiff during insertion and soft during chronic use. To date, no one has demonstrated a 3D softening electrode array. Current technologies, made from silicon can be miniature, high-density, batch-fabricated and capable of supporting active on-board electronics. Silicon, however, is a brittle material, and while its stiffness allows for easy implant into soft neural tissue, it presents a serious mechanical mismatch between the implanted device and the soft neural tissue after implant. Other current penetrating flexible electronics technologies have been limited to 2D structures. In this Phase I SBIR proposal, Qualia Inc. will explore the feasibility of adapting its planar processing thin film photolithography technologies into a third dimension. Previous SBIR funding from DARPA helped establish our shape memory polymer (SMP) substrates as candidates for chronically viable neural implants. However, our past studies have been limited to 2D devices. In this proposal, which is focused on innovative packaging technologies, we aim to create 3D architectures which fill a critical void in the neuroscience research community.